The invention relates to a method for retinal diagnosis. The invention furthermore relates to an apparatus for performing the method.
Such a method is known from EP 1 487 322 B1, which is for examining cavities of the retina in an eye and determining the cavity wall thickness. Laser scanning is used to determine the external diameter and the internal diameter of the cavity, and then the wall thickness of the cavity is determined from the data thus obtained. The external cavity diameter is determined from the data of a reflectivity image, and the internal diameter is determined from the data of a laser Doppler image according to the diameter of the blood column moved. Comprehensive examination and diagnostics of the retina is not possible without anything further. The laser scanning technology is used for producing reflectivity images, angiography images, and auto-fluorescent images of the retina. A laser beam with a specific wavelength scans the retina point by point in a two-dimensional field, and the result is continuous live images or reference images, 10 to 50 images per second being typical. The angiography, in particular in the form of fluorescein angiography (FA) and indocyanine green angiography (ICGA), is an important diagnostic procedure in which essentially two-dimensional images of the retina surface, and where necessary, deeper layers of the retina, are produced by illuminating and scanning in a point-by-point manner. Furthermore, such planar images can be produced using flat illumination and acquisition by a suitable imaging sensor such as for instance a CCD (charge coupled device) camera or a fundus camera. Moreover, spectral-domain optical coherence tomography (OCT) is used for retinal diagnosis; it provides two-dimensional slice images essentially perpendicular to the retinal surface, so-called B scans, that are combined linearly from A scans that go deep into the fundus. Two different apparatus are required for producing the aforesaid planar images and the depth slice images, and this results in significant complexity. In terms of the various known methods, examining and diagnosing the retina of the eye is very demanding for an examiner, but also for a patient, and in addition it is time consuming, sometimes requiring that examinations be performed successively using different apparatus.
Proceeding from this state of the art, the underlying object of the invention is to propose a method that makes possible, in a simple manner, a comprehensive examination and diagnosis of the retina of the eye. It should be possible to perform the method without a problem and in a functionally safe manner, and to provide reliable results with a low degree of complexity while rendering diagnosing easier for the examiner. The apparatus for performing the method should have a simple and/or functionally safe structure, should not be complex to operate, and should enable optimized and/or comprehensive retinal diagnosis.